Since 1996, every automobile manufactured in the United States is required to have an onboard diagnostics (OBD) system, including an OBD connector. The currently-required system is a second generation, OBD-II system.
The OBD-II connector, or port, has sixteen (16) pin receptacles in two rows of eight, as shown in FIG. 9. According to current requirements, the OBD-II connector must be positioned within two feet of the steering wheel, unless an exemption is approved for the manufacturer, in which case the connector must still be generally within reach of the driver.
The OBD system enables the vehicle to self-diagnose potential problems with the vehicle, and report the same, such as to diagnostic equipment that can be connected to the system. The OBD system allows, for instance, the vehicle owner or a repair technician access to state-of-health information for various vehicle sub-systems.
The OBD-II standard specifies a type of diagnostic connector and its pinout, electrical signaling protocols available, and a messaging format. Regarding assigned pins, there is, for example, a pin providing power, from the vehicle battery, which can be used for a scan tool. This eliminates need to connect the scan tool to a separate power source.
Modern vehicles are also increasingly being outfitted with short-range, medium-range, and long-range communication capabilities. The capabilities are generally provided by an original-equipment-manufacturer (OEM) equipment of the vehicle.
An example communication system is a dedicated short-range communications (DSRC) system. DSRC can be used for, among other uses, transmission of emergency-related communications to and from the vehicle.
Communication and safety systems require a power source, for powering the transceiver, and an antenna resource for improving reception capabilities.
The OBD-II system provides convenient access to power and a reception antenna. And some of the pins of the OBD-II connector are open for use. Regulatory restrictions, though, prohibit using the OBD-II to carry proprietary signals, such as those of an onboard wireless communications system (e.g., DSRC system) because using the OBD connector to carry proprietary signals could interfere with OBD operations, such as scanning-tool or other diagnostic functions.